Earth and Planetary Science Letters最新文献

{"title":"Porphyritic olivine chondrules with enstatite chondrite isotopic composition as a main building block of Earth","authors":"Yves Marrocchi ,&nbsp;Tahar Hammouda ,&nbsp;Maud Boyet ,&nbsp;Guillaume Avice ,&nbsp;Alessandro Morbidelli","doi":"10.1016/j.epsl.2025.119337","DOIUrl":"10.1016/j.epsl.2025.119337","url":null,"abstract":"<div><div>The nature and origin of the Earth's building blocks remain intensely debated. While enstatite chondrites (ECs) were formed from a reservoir with an isotopic composition of major elements similar to that of the Earth, they nevertheless exhibit significant chemical differences. Specifically, the Earth is enriched in refractory elements and depleted in moderately volatile elements compared to ECs. By reevaluating the budget of rare earth elements in enstatite chondrites, we show that EC chondrule precursors correspond to early condensates formed in the inner protoplanetary disk. Taking condensation models into account, we propose that these condensates consist primarily of olivine, which was subsequently transformed into enstatite due to gas-melt interactions during chondrule formation. We show that the accretion of the Earth from olivine-rich EC chondrules, which underwent shorter gas-melt interactions compared to those present in ECs, satisfactorily reproduces its chemical ratios (i.e., Mg/Si, Al/Si, Na/Si, Ti/Si, Ca/Si) and oxygen isotopic composition. This difference in the duration of gas-melt interactions in the protoplanetary disk had thus major consequences on the chemical composition of the planetesimals accreted by planetary embryos. Our approach thus addresses the chemical divergence between Earth and ECs without altering their isotopic compositions, while also supporting planet formation models involving large embryos formed in the inner protoplanetary disk.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"659 ","pages":"Article 119337"},"PeriodicalIF":4.8,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the stratigraphic record of glacioeustatic sea-level rise and sediment starvation following Snowball Earth","authors":"A.R. Nordsvan ,&nbsp;K.W. Bauer ,&nbsp;C.L. Colleps ,&nbsp;R.N. Mitchell ,&nbsp;N.R. McKenzie","doi":"10.1016/j.epsl.2025.119332","DOIUrl":"10.1016/j.epsl.2025.119332","url":null,"abstract":"<div><div>Cap carbonates overlying Neoproterozoic Snowball Earth glacial deposits are often interpreted as reflecting either rapid deglaciation or prolonged periods of post-glacial sediment starvation. To evaluate these contrasting depositional models, we use 3D stratigraphic forward modeling to assess the impact of glacioeustatic sea-level rise on continental shelf sedimentation. Our models, which incorporate real-world sediment supply data and margin configurations, demonstrate that the rapid, high-amplitude sea-level rise characteristic of a Snowball Earth deglaciation triggers prolonged periods of terrigenous sediment starvation on continental shelves. The duration of this sediment-starved period is positively correlated with shelf accommodation (highest in glacially influenced settings) and negatively correlated with sediment supply (lower in post-glacial settings). These results suggest that extensive hiatuses would have occurred across many post-Snowball Earth margins. While our models do not simulate the geochemical mechanisms driving cap carbonate precipitation, they show that general carbonate deposition during the siliciclastic hiatus is typically sharp-based, thickens basinward, and has a more gradational upper contact. These trends align with observations from Australian cap carbonate sequences, suggesting that sediment starvation played a role in their genesis. This research underscores the potential for extended periods of sediment starvation following Snowball Earth events and highlights the critical need to investigate the broader implications of such events on Earth's systems during this pivotal phase of its evolution.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"659 ","pages":"Article 119332"},"PeriodicalIF":4.8,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenesis of Chang'E-6 basalts and implication for multi-episode volcanism in the lunar farside basin","authors":"Dehan Shen ,&nbsp;Shijie Li ,&nbsp;Shaolin Li ,&nbsp;Yingkui Xu ,&nbsp;Yang Li ,&nbsp;Mingbao Li ,&nbsp;Deliang Wang ,&nbsp;Ronghua Pang ,&nbsp;Yuwei Zhang ,&nbsp;Zhipeng Han","doi":"10.1016/j.epsl.2025.119335","DOIUrl":"10.1016/j.epsl.2025.119335","url":null,"abstract":"<div><div>Mare basalts are products of lunar mantle via partial melting, and hence viewed as crucial probes of the mantle's composition and thermal state. While previous mission-returned lunar samples have provided valuable insights into the composition and structure of the lunar interior, our understanding remains limited because all samples have been collected from the lunar nearside. Consequently, numerous scientific questions about the Moon's dichotomy remain unresolved. In June 2024, China's Chang'E-6 (CE-6) mission successfully returned the first-ever samples from lunar farside, which marks a new era in lunar science. In this work, we examine the petrography, mineralogy, and geochemistry of CE-6 basaltic fragments. Our results reveal that the basaltic fragments at the CE-6 landing site exhibit variable chemical compositions, ranging from very low-Ti to low-Ti types. The diversity in the petrogenesis of these basaltic rocks demonstrates significant differences in the mantle source and subsequent magmatic processes. Combined with remote sensing data, these findings indicate a complex thermal evolution for the southern mare of the Apollo basin in the South Pole-Aitken (SPA) basin, which experienced at least three episodes of volcanism. Additionally, the broad variation in TiO₂ content suggests the possibility of even more episodes of volcanism occurred and more types of basalts existed in this farside basin of the Moon. Furthermore, the multi-episodes magmatism occurred in the lunar farside basin, suggests that spatial variations in magma production rates across the Moon's interior may be negligible. The petrogenetic modeling of CE-6 basaltic fragments demonstrates that incompatible element concentrations and mineral modes are likely to be similar across lunar nearside to farside mantle. In contrast, the lunar crust appears to play a critical role in controlling basaltic magma eruptions on the farside surface.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"659 ","pages":"Article 119335"},"PeriodicalIF":4.8,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamics of light elements stratification in the earth's outer core and implications","authors":"Jibamitra Ganguly","doi":"10.1016/j.epsl.2025.119333","DOIUrl":"10.1016/j.epsl.2025.119333","url":null,"abstract":"<div><div>Thermodynamic calculations, accounting for the effects of changing P, T, and gravitational potential, have been performed to determine the radial distribution of the light elements O, S, Si and C in the outer core of the Earth. It is found that under equilibrium conditions the light elements should be stratified within the top 200–400 km of the outer core, increasing rapidly in concentration with radial distance within this range. The high oxygen content of ∼13 wt % at the top of the core inferred from consideration of core-mantle equilibrium matches the calculated O-concentration profile for the bulk O content of ∼ 2 wt %. The evolution of the core toward the state of thermodynamic equilibrium prior to the destabilizing effect of vigorous convection triggered by the inner core formation provides a possible explanation of the stratification of the core near the core-mantle boundary (CMB), as inferred from geophysical data. Similar stratification should also be expected within the core of Mars and other planets with sufficiently large mass of liquid iron, with that in the former being much thicker than in the Earth's core, thereby possibly causing early extinction of its magnetic field. Because of the potential stratification of K into the top part of the core, the role of ⁴⁰K to ⁴⁰Ar decay as an energy source to power the geodynamo becomes problematic.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"659 ","pages":"Article 119333"},"PeriodicalIF":4.8,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic constraints on devolatilization of variably altered oceanic ultramafic rocks during subduction: Implications for subarc mantle oxidation","authors":"Weigang Peng ,&nbsp;Katy A. Evans ,&nbsp;James A.D. Connolly ,&nbsp;Yi-Bing Li ,&nbsp;Han Hu ,&nbsp;Lifei Zhang","doi":"10.1016/j.epsl.2025.119308","DOIUrl":"10.1016/j.epsl.2025.119308","url":null,"abstract":"<div><div>Fluids released by devolatilization of subducted serpentinites at subarc depths trigger partial melting of the overlying mantle wedge and contribute to arc magmatism. The subarc mantle is more oxidized relative to the oceanic mantle, but the potential role of fluids derived from serpentinites during subduction in this oxidation remains contentious. Here, we compile bulk compositions of variably altered oceanic ultramafic rocks at slow- to ultraslow-spreading mid-ocean ridges worldwide, including partially and completely serpentinized ultramafic rocks, carbonate-bearing serpentinites (referred to as ophicarbonates), and talc-altered serpentinites. Using thermodynamic modeling, we quantify the oxygen fugacity (<em>f</em>O₂) of fluids produced during breakdown of antigorite, chlorite, and talc, which are the major water carriers in these lithologies under subarc conditions, along typical subduction geotherms. Results show that the redox states of the rocks prior to subduction play an important role in the <em>f</em>O₂ of the deep-released fluids and that the subduction geotherms play a minor role. Partially and completely serpentinized ultramafic rocks and ophicarbonates with initial Fe³⁺/Fe_total ratios of 0.45, 0.84, and 0.78 generate fluids with increasing <em>f</em>O₂ to 2.4–2.8, 3.7–4.0, and 3.0–3.4 log units above the fayalite–magnetite–quartz (FMQ) buffer, respectively, during antigorite dehydration, which remains almost constant during chlorite dehydration. These calculations, combined with previous experimental and modeling results, suggest that oxidized fluids are liberated through antigorite and chlorite breakdown in subducted serpentinites, and the fluid <em>f</em>O₂ may be positively linked to the initial bulk Fe³⁺/Fe_total ratios. Inconsistency occurs between the modeling results and the sample-based study, given that the transformation of S-bearing phases in natural rocks is likely more complicated. In contrast, talc-altered serpentinites have relatively low Fe³⁺/Fe_total ratios and total Fe contents, and fluids characterized by decreasing <em>f</em>O₂ to ∼0.5 log units below the FMQ buffer can be produced during primary devolatilization. Quantification of fluid-mediated mass transfer indicates that dehydration of antigorite and chlorite in partially serpentinized ultramafic rocks in subducted oceanic slabs can oxidize the subarc mantle on typical subduction timescales, particularly along the cold to intermediate geotherms.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"659 ","pages":"Article 119308"},"PeriodicalIF":4.8,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topographic signature of magmatic emplacement at depth: The case of the Larderello-Travale Geothermal area (Northern Apennines, Italy)","authors":"Riccardo Lanari ,&nbsp;Marco Bonini ,&nbsp;Andrea Sembroni ,&nbsp;Samuele Papeschi ,&nbsp;Chiara Del Ventisette ,&nbsp;Adam G.G. Smith ,&nbsp;Matteo Lupi ,&nbsp;Domenico Montanari","doi":"10.1016/j.epsl.2025.119290","DOIUrl":"10.1016/j.epsl.2025.119290","url":null,"abstract":"<div><div>Magmatism is an important driver of topographic change. However, our understanding of its long-term impact on topographic evolution remains incomplete. We investigate the potential surface response to magmatic intrusions in the active Larderello-Travale geothermal field, in the northern Italian Apennines. Here, multiple igneous bodies have intruded since the Pliocene causing at least 500 m of large-wavelength surface uplift. We combine available stratigraphic information with a new set of morphological analyses and river inversion models to quantify, the magnitude, rate, and spatial distribution of uplift throughout the last 3.5 Ma. In describing the style of the uplift, we report a temporal and spatial correlation between rock uplift pulses and middle crust magma injections.</div><div>For the first time in this area, we document the positive feedback between different magma injections and local surface responses (e.g., river incision). We use a surface evolution model to suggest a potential scenario of magma emplacement over time. In this sense, we suggest that at the very beginning, uplift rates were higher to the north of the current thermal anomaly, and only after the uplift migrated further south. This could indicate that the deep source of the Larderello-Travale geothermal field might not be precisely located underneath the current thermal anomaly. This would allow undocumented plutons (deep enough such that they are not evidenced by shallow thermal anomalies) to be tracked, leading to more conscious and effective strategies for geothermal exploration.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"659 ","pages":"Article 119290"},"PeriodicalIF":4.8,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"H2O in nominally anhydrous mineral inclusions in diamonds and the volatile composition of diamond forming media","authors":"Andrea Curtolo ,&nbsp;Maxwell C. Day ,&nbsp;Francesca Innocenzi ,&nbsp;Nathalie Bolfan-Casanova ,&nbsp;Martha G. Pamato ,&nbsp;Simon Falvard ,&nbsp;Fabrizio Nestola ,&nbsp;Jeff W. Harris ,&nbsp;Davide Novella","doi":"10.1016/j.epsl.2025.119311","DOIUrl":"10.1016/j.epsl.2025.119311","url":null,"abstract":"<div><div>Many studies have investigated the H₂O content of mantle minerals in xenoliths, which in various cases show evidence of metasomatism, implying that the measured H₂O contents may reflect these modification processes rather than the H₂O content in the environment where they were sourced. In this work, the H₂O content of 118 mineral inclusions in lithospheric diamonds, that are shielded from metasomatic and alteration events by their diamond host, was investigated.</div><div>Most of the inclusions studied here are clinopyroxene and garnet of eclogitic and peridotitic paragenesis and their H₂O content was determined by recording Fourier Transform Infrared (FTIR) spectra of each inclusion within their diamond host. Additional analyses conducted on seven inclusions that were extracted from their diamond host show good agreement with the analysis performed while still trapped inside the diamond, confirming the validity of the H₂O contents determined for the inclusions still trapped by their diamond host. The measured H₂O contents range from 0 to 550 ppm wt. with eclogitic inclusions showing a higher H₂O content with respect to their peridotitic counterparts. On average, clinopyroxene has the highest H₂O content compared to all other inclusion minerals (with average H₂O content of 110 ppm wt. and 61 ppm wt. for eclogitic and peridotitic samples, respectively). The H₂O contents of mineral inclusions in diamonds studied here and from the literature are much lower than those reported for cratonic mantle xenoliths. This difference may be due to (i) sampling bias, (ii) metasomatism subsequent to diamond formation, or (iii) lithospheric mantle involved in diamond formation not being representative of the average cratonic lithosphere (i.e., with a different H₂O activity). Modelled H diffusion in mineral inclusions in diamonds at the pressure and temperature conditions of diamond formation is fast, indicating complete H₂O re-equilibration with the diamond forming medium. It follows that the diamond forming medium must be a silicate melt with a low H₂O content, a carbonatitic melt and/or a fluid characterized by a low H₂O activity.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"658 ","pages":"Article 119311"},"PeriodicalIF":4.8,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compositional outcomes of Earth formation from a narrow ring","authors":"Katherine I. Dale ,&nbsp;Alessandro Morbidelli ,&nbsp;David C. Rubie ,&nbsp;David Nesvorný","doi":"10.1016/j.epsl.2025.119334","DOIUrl":"10.1016/j.epsl.2025.119334","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The origin of Earth's formation material remains controversial. Here we address the problem from the elemental point of view. We use an approach similar to that of &lt;span&gt;&lt;span&gt;Rubie et al. (2015)&lt;/span&gt;&lt;/span&gt;, with the technical improvements presented in &lt;span&gt;&lt;span&gt;Dale et al. (2023)&lt;/span&gt;&lt;/span&gt; to simulate the chemical evolution of the Earth's mantle during a series of metal-silicate partial equilibration events associated with accretional collisions. However, we introduce two radical differences. First, we consider the dynamical model in which Earth forms from a dense ring of planetesimals and planetary embryos near 1 AU, with a low-density extension of the planetesimal population into the asteroid belt. Second, we divide the ring and asteroid belt population into four zones. The zone closest to the Sun is assumed to be populated by planetesimals and embryos enriched in elements more refractory than Si relative to CI concentrations and fully depleted in volatile elements including S and C. This material is not sampled in the meteorite record, except potentially in angrites. Moving further away from the Sun, the remaining three zones are populated by material with the compositions of enstatite chondrites, ordinary chondrites and CI chondrites respectively. Using this model, we fit the chemical composition of the bulk silicate Earth in terms of relative abundances of the oxides of Al, Mg, Fe, Si, Ni, Co, Nb, V, Cr, W, Mo and C by adjusting the boundaries of the above compositional zones and the refractory enrichment in the innermost zone thus giving us four compositional free parameters. A fifth and final fitting parameter concerns the depth of planetesimal equilibration in a magma ocean produced following a giant impact. We considered twenty-two simulations of the ring model, all of which produced at least one planet of similar mass and semi-major axis as the Earth. Each simulation of the chemical evolution of the Earth assumed either an initially hot or cold target for collisions producing a total of forty-eight Earth analogues. Seventeen of the analogues represent a planet with bulk mantle chemistry quite similar to that of the observed bulk silicate Earth (BSE) despite their differing hierarchical growth sequences. However, these differences in the sequence, size and initial position of the impactors result in different values of the five fitting parameters. This equates to differences in the proportion of each meteorite type required to obtain a chemical composition similar to the BSE, though some similarities remain such as the requirement for the Earth to accrete the majority (60-80%) of its material from the innermost refractory enriched region. This implies that, paired with the right hierarchical growth sequence and with some constraints, more than one ring model compositional structure can produce an Earth analogue consistent with the BSE, with very similar final mantle compositions for all considered elements.&lt;/div&gt;&lt;/div","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"658 ","pages":"Article 119334"},"PeriodicalIF":4.8,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-precision geochronology of the Equatorial Atlantic Magmatic Province (EQUAMP): Temporal correlations with the Paraná-Etendeka Magmatic Province and the Weissert Event","authors":"Alisson L. Oliveira ,&nbsp;Maria Helena B.M. Hollanda ,&nbsp;Mark D. Schmitz ,&nbsp;Antomat A. Macêdo Filho ,&nbsp;Elisabetta Erba ,&nbsp;James L. Crowley","doi":"10.1016/j.epsl.2025.119330","DOIUrl":"10.1016/j.epsl.2025.119330","url":null,"abstract":"<div><div>The Equatorial Atlantic Magmatic Province (EQUAMP) is an intrusive large igneous province (LIP) related to the dismembering of the West Gondwana supercontinent and early opening stage of the South Atlantic Ocean. Here, we present the first set of high-precision (at the 100 ka-level) U-Pb zircon geochronology for the EQUAMP by the chemical abrasion isotope dilution thermal ionization mass spectrometry method. Based on our results, the EQUAMP was emplaced in a short time interval, between 133.805 ± 0.021 Ma and 133.071 ± 0.031 Ma and appears to be coeval with the Paraná Etendeka Magmatic Province (∼134.5–132.0 Ma). Both LIPs are currently exposed at the margins of the South Atlantic Ocean and could have jointly contributed greenhouse gasses and fresh mafic exposures susceptible to chemical weathering that ultimately fertilized the oceans, cooled the Earth, affected calcareous nannoplankton and produced a paleoclimate disturbance — the Valanginian Weissert Event.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"658 ","pages":"Article 119330"},"PeriodicalIF":4.8,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nature of space-weathered rims on Chang'e-5 lunar soil grains","authors":"Zhi Cao ,&nbsp;Xi Wang ,&nbsp;Yun Chen ,&nbsp;Chen Li ,&nbsp;Sizhe Zhao ,&nbsp;Yang Li ,&nbsp;Yuanyun Wen ,&nbsp;Qi He ,&nbsp;Zhiyong Xiao ,&nbsp;Xiongyao Li ,&nbsp;Long Xiao ,&nbsp;Jianzhong Liu","doi":"10.1016/j.epsl.2025.119327","DOIUrl":"10.1016/j.epsl.2025.119327","url":null,"abstract":"<div><div>The space weathering processes modify the microstructure and physicochemical properties of the surface of regolith mineral grains. We report microcraters and space-weathered rims on the surface of plagioclase, pyroxene, olivine, ilmenite and troilite grains in Chang'e-5 scooped lunar soil by electron microscopy. Micro-analysis shows that low-speed secondary impact events indicated by microcraters dominated the evolution of Chang'e-5 regolith materials, which may have driven the formation of a potential microscale redox environment under a special mineral combination. Solar wind and cosmic ray irradiation lead to significant differences in space-weathered rims of mineral surfaces. This indicates the correlation between the nature of different space-weathered rims and the inherent structure and composition of minerals. According to the statistical correlation between space-weathered rim width and track density, the average exposure ages of plagioclase and olivine in Chang'e-5 lunar soil are <span><math><mrow><mn>2</mn><mo>.</mo><msubsup><mn>180</mn><mrow><mo>−</mo><mn>0.222</mn></mrow><mrow><mo>+</mo><mn>0.229</mn></mrow></msubsup></mrow></math></span> Ma and <span><math><mrow><mn>0</mn><mo>.</mo><msubsup><mn>842</mn><mrow><mo>−</mo><mn>0.469</mn></mrow><mrow><mo>+</mo><mn>1.120</mn></mrow></msubsup></mrow></math></span> Ma, respectively. This rule applies to regolith materials with short exposure time. The in situ mineralogical evidence clarifies that compared with Apollo mature lunar soil, Chang'e-5 lunar soil seems to have undergone weaker space weathering modification and shorter exposure history, and the essence is a weakly space-weathered lunar soil from young basalt. The nature of the space-weathered rims on the mineral surface of Chang'e-5 lunar soil reflects the response of regolith material to space weathering in a short exposure history, which is of great significance for the interpretation of spectral data of returned samples.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"658 ","pages":"Article 119327"},"PeriodicalIF":4.8,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}